Filter internal valuation comments from public api

Why:

Internal valuation comments are only for admins and valuators,
not for the public view.

How:

Adding a `not_valuations` scope and use it at the `public_for_api` one

app/models/comment.rb

@@ -33,7 +33,8 @@ class Comment < ActiveRecord::Base
   end
   scope :sort_by_flags, -> { order(flags_count: :desc, updated_at: :desc) }
   scope :public_for_api, -> do
-    where(%{(comments.commentable_type = 'Debate' and comments.commentable_id in (?)) or
+    not_valuations
+      .where(%{(comments.commentable_type = 'Debate' and comments.commentable_id in (?)) or
             (comments.commentable_type = 'Proposal' and comments.commentable_id in (?)) or
             (comments.commentable_type = 'Poll' and comments.commentable_id in (?))},
           Debate.public_for_api.pluck(:id),
@@ -50,6 +51,8 @@ class Comment < ActiveRecord::Base
   scope :sort_by_oldest, -> { order(created_at: :asc) }
   scope :sort_descendants_by_oldest, -> { order(created_at: :asc) }
 
+  scope :not_valuations, -> { where(valuation: false) }
+
   after_create :call_after_commented
 
   def self.build(commentable, user, body, p_id = nil)

spec/factories.rb

@@ -465,6 +465,10 @@ FactoryBot.define do
     trait :with_confidence_score do
       before(:save) { |d| d.calculate_confidence_score }
     end
+
+    trait :valuation do
+      valuation true
+    end
   end
 
   factory :legacy_legislation do

spec/models/comment_spec.rb

@@ -187,5 +187,11 @@ describe Comment do
 
       expect(described_class.public_for_api).not_to include(comment)
     end
+
+    it "does not return internal valuation comments" do
+      valuation_comment = create(:comment, :valuation)
+
+      expect(described_class.public_for_api).not_to include(valuation_comment)
+    end
   end
 end